Process for scoring and folding steel foil-paperboard laminates



March 25, 1969 c. E. PALMER PROCESS FOR SCORING AND FOLDING STEEL FOIL-PAPERBOARD LAMINATES Filed July 29. 1966 Q ##WA 7 977467 INVENTOR. CHARLES EPALMER hisAGENT United States Patent 3,434,399 PROCESS FOR SCORING AND FOLDING STEEL FOIL-PAPERBOARD LAMINATES Charles E. Palmer, Somers, Conn., assignor to Jones &

Laughlin Steel Corporation, Pittsburgh, Pa., a corporation of Pennsylvania Filed July 29, 1966, Ser. No. 573,154 Int. Cl. B31b 1/26; B65d 5/02 US. Cl. 9358 Claims ABSTRACT OF THE DISCLOSURE A process for folding a steel foil-paperboard laminate comprising scoring the laminate on the paperboard side sutficiently to deform the underlying steel foil and folding the laminate along the score line so that the resultant bead produced forms on the steel foil lamina.

The use of steel foil-paperboard laminates in packaging, building and decorating as well as for other consumer and industrial applications has been suggested. The application of these laminates to purposes as have been suggested would invariably require that the laminates at some time be folded. However, known methods for scoring and folding paperboard have proven to be unsatisfactory when applied to steel foil-paperboard laminates. There-fore, the object of my invention is to provide a method for scoring and folding these laminates in a manner so as to produce acceptable folds.

Generally, the type of laminates to which my invention is to be applied are those having a steel foil lamina and a paperboard lamina normally joined by an adhesive. Although my invention has applicability to steel foil of various gauges and to papenboard of various caliper size, it is considered that the most prevalent use of my invention will be to laminates wherein the steel foil is of about .003 inch gauge or less and the paperboard is of about 9 to about point calipers. Further, the steel foil used will generally be full hard, that is, steel foil which has not been annealed after having been worked to final gauge, although my invention is equally applicable to steel foil which has been annealed after having been worked to final gauge.

Steel foil-paperboard laminates have special advantages over other metallic-paperboard laminated products because of the high tensile strength and abrasion resistance of steel foil as compared to other types of metal foil. The strength of such laminates is, of course, also greater than the paperboard alone.

In the drawing FIGURE 1 is an enlarged cross-sectional view of a steel foil-paperboard laminate after it has been scored according to my invention. FIGURE 2 is a cross-sectional view of the same laminate subsequent to folding of the same according to my invention,

The use of these laminates as is contemplated for example in the package arts requires, as has been noted, that the laminated product be folded. Thus, for example a steel foil-paperboard laminate blank is scored, folded and fastened so as to provide a container for various types of materials. The conventional method of scoring and folding paperboard is to score the paperboard in such a manner so that the resultant bead produced upon folding is on the inside of the fold. That is, the board is scored on the side which forms the outside of the fold. Paperboard requires this treatment to eliminate fiber separation on the inside of the score. Therefore, paperboard is of necessity folded against the bead. In attempting to fold steel foil-paperboard laminates in this manner, that is, against the bead, it has been found that the fold wanders at will across the scored line and for particular steel gauges wanders completely away from it, thereby resulting in an unsatisfactory fold. I have discovered that a more desirable method of folding steel laminates is to score the laminate on the paperboard side and then fold the laminate so as to cause the bead of the fold to be on the outside or steel foil side of the fold. When scoring thepaperboard lamina, it is necessary that it be scored sufliciently to deform the steel foil lamina. By making the fold against the indentation of the score, this allows the stretch strength line of the steel at the score to form the fold line with no resistance from an inside bead.

Thus, With reference to the drawing, FIGURE 1 illustrates in cross-section a typical steel foil-paperboard laminate to which my method is to be applied. The paperboard lamina 2 is scored, as has been previously noted, sufiiciently to deform the steel foil lamina 1 as shown in the figure. The laminate is then folded so as to cause the bead of the fold to be on the outside or steel foil side of the fold thereby producing a fold in cross-section as is shown in FIGURE 2. The latter figure illustrates the formation of bead 3 on the steel foil lamina and the formation of the depression 4 on the paperboard formed as a result of scoring.

The means used to form the score lines is not significant and may be any means known to those skilled in the art.

In disclosing the invention specific descriptions were resorted to in the interest of clarity, but the scope of my invention is not to be limited by such descriptions and is to be determined by the appended claims.

I claim:

1. A- process for folding a steel foil-paperboard laminate having a paperboard lamina and a steel foil lamina comprising the steps of scoring said paperboard lamina sufliciently to deform the steel foil lamina and folding said laminate along said score so that the resultant bead produced forms on the steel foil lamina.

2. The process of claim 1 wherein the steel foil is of a gauge less than about .003 inch.

3. The process of claim 1 wherein the paperboard is from about 9 point to about 20* point calipers.

4. The process of claim 1 wherein the steel foil is of a gauge less than about .003 inch and the paperboard is from about 9 point to about 20 point calipers.

5. The process of claim 1 wherein the steel foil is full hard, of a gauge less than about .003 inch and the paperboard is from about 9 point to about 20 point calipers.

6. A process of preparing a steel foil-paperboard laminate having a paperboard lamina and a steel foil lamina for folding, comprising the step of scoring said paperboard lamina at a predetermined location sufficiently to deform the steel foil lamina.

7. The process of claim 6 wherein the steel foil is of a gauge less than about .003 inch.

8. The process of claim 6 wherein the paperboard is from about 9 point to about 20 point calipers.

9. The process of claim 6 wherein the steel foil is of a gauge less than about .003 inch and the paperboard is from about 9 point to 20 point calipers.

10. The process of claim 6 wherein the steel foil is full hard, of a gauge less than about .003 inch and the paperboard is from about 9 point to about 20 point calipers.

References Cited UNITED STATES PATENTS 1,302,831 5/1919 Naugler 93-581 1,67 3, 109 6/ 1928 Fenstermacher. 3,297,225 1/ 1967 Bransten.

BERNARD STICKNEY, Primary Examiner.

US. Cl. X.R. 2293.5 

